[tcpm] About the urgent pointer...
David Borman <david.borman@windriver.com> Wed, 11 March 2009 20:55 UTC
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From: David Borman <david.borman@windriver.com>
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Subject: [tcpm] About the urgent pointer...
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Hello, One of the items on the TCPM agenda for IETF 74 is the TCP Urgent pointer. I want this to be a very focused discussion around one question: Should the urgent pointer point to the last byte of urgent data, or the first byte of non-urgent data? RFC 793 has one place (p. 17) where it says that it is the first byte of non-urgent data, and at least two places (p. 41 and p. 56) where it says that it is the last byte of urgent data. Though RFC 961 and RFC 1122 resolve this ambiguity and are clear that the urgent pointer is defined to point to the last byte of urgent data, as draft-gont-tcpm- urgent-data-01 points out most systems actually implement it as the first byte of non-urgent data. This goes back to the original BSD code from CSRG. So, the question is *not* what do the RFCs say, because they are clear. The question is, what do we do about the mismatch between what the RFCs say, and what is generally implemented? -David Borman
- [tcpm] About the urgent pointer... David Borman
- Re: [tcpm] About the urgent pointer... Fernando Gont